Catalysts and processes for conversion of 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113) to 1, 1, 2-trifluoroethane (HFC-143)

Abstract

In some embodiments, HFO-132, and in particular HFO-1132E, may be produced from 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113), and in particular HFO-1132E may be produced from 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113). In a first step, 1, 1, 2-trifluoroethane (HFC-143) is produced by hydrogenating 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113) by reacting with hydrogen in the presence of a catalyst to produce 1, 1, 2-trifluoroethane (HFC-143). The highly exothermic hydrogenation step may be moderated by diluting the catalyst and / or by diluting the 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113) feedstock. The 1, 1, 2-trifluoroethane (HFC-143) may then be dehydrofluorinated in the presence of a catalyst to produce trans-1, 2-difluoroethylene (HFO-1132E) and / or cis-1, 2-difluoroethylene (HFO-1132Z). The cis-1, 2-difluoroethylene (HFO-1132Z) may then be isomerized to produce a trans-1, 2-difluoroethylene (HFO-1132E), and then, the cis-1, 2-difluoroethylene (HFO-1132E) may be isomerized.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Patent Application No. 18 / 807,095, filed August 16, 2024, entitled “Catalyst and Method for Converting 1,1,2-Trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143)”, which claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 534,000, filed August 22, 2023, entitled “Catalyst and Method for Converting 1,1,2-Trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143)”, under Title 35, Section 119(e), the entire disclosure of which is expressly incorporated herein by reference. Technical Field

[0003] This disclosure relates to catalysts and methods for producing trans-1,2-difluoroethylene (HFO-1132E) from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and more particularly to catalysts and methods for converting 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) into an intermediate of 1,1,2-trifluoroethane (HFC-143) in the process of producing trans-1,2-difluoroethylene (HFO-1132E). Background Technology

[0004] Recently, increased applicability of 1,2-difluoroethylene (HFO-1132) has been discovered for a variety of applications. HFO-1132 can exist as a mixture of two geometric isomers, namely the E-isomer (trans-isomer) and the Z-isomer (cis-isomer), which can be used alone or in various proportions. Potential end-use applications of 1,2-difluoroethylene (HFO-1132) include refrigerants, used alone or in blends with other components, as a solvent for organic materials, and as a chemical intermediate in the synthesis of other halogenated hydrocarbon solvents.

[0005] An improved method is desired for producing 1,2-difluoroethylene (HFO-1132), and in particular trans-1,2-difluoroethylene (HFO-1132E). Summary of the Invention

[0006] The production of trans-1,2-difluoroethylene (HFO-1132E) from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) involves a multi-step catalytic process.

[0007] In the first step, 1,1,2-trifluoroethane (HFC-143) is produced by hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with hydrogen in the presence of a catalyst to produce 1,1,2-trifluoroethane (HFC-143). This 1,1,2-trifluoroethane (HFC-143) can then be dehydrofluorinated in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z). This cis-1,2-difluoroethylene (HFO-1132Z) can then be isomerized to produce trans-1,2-difluoroethylene (HFO-1132E).

[0008] This disclosure provides catalysts and methods for controlling the highly exothermic reaction in the first step described above, namely, producing 1,1,2-trifluoroethane (HFC-143) by hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with hydrogen in the presence of a catalyst.

[0009] In the first method, the catalyst used in the aforementioned reaction can be diluted with a diluent material that serves as an endothermic medium to help manage the heat generated during the reaction.

[0010] In the second method, before or during the reaction, the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) reactant can be combined with a certain amount of a raw material diluent (such as a non-reactive gas) and / or a raw material diluent in the form of an organic molecule (such as 1,1,2-trifluoroethane (HFC-143)), which can be a product separate from the reaction itself or introduced into the reaction independently from an external source.

[0011] When used alone or in combination with each other, each of the above methods can increase the selectivity for the desired product 1,1,2-trifluoroethane (HFC-143) and / or the selectivity for the desired intermediate, and / or decrease the selectivity for the undesirable byproduct.

[0012] In one form, this disclosure provides a method for producing 1,1,2-trifluoroethane (HFC-143), the method comprising: hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reacting it with hydrogen in the presence of a catalyst to produce 1,1,2-trifluoroethane (HFC-143), said catalyst comprising: a catalytic material comprising 0.1 wt% to 1.0 wt% of the catalytic metal supported on the support based on the total weight of the catalytic metal and the support; and a diluent material, wherein the amount of said catalytic material is 5 vol% to 70 vol% based on the total volume of said catalytic material and said diluent material.

[0013] In the above method, the carrier can be α-alumina.

[0014] In another form, this disclosure provides a palladium metal catalyst that can be used to hydrogenate 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reacting with hydrogen to produce 1,1,2-trifluoroethane (HFC-143), the catalyst comprising: a catalytic material comprising 0.1 wt% to 1.0 wt% palladium metal supported on an alumina (Al2O3) support based on the total weight of the catalytic metal and the support; and a diluent material, wherein the amount of the catalytic material is 5 vol% to 70 vol% based on the total volume of the catalytic material and the diluent material.

[0015] In the above catalyst, the support can be α-alumina.

[0016] In another form, this disclosure provides a method for producing 1,1,2-trifluoroethane (HFC-143), the method comprising combining 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with a feedstock diluent to form a reaction mixture; and

[0017] The 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the reaction mixture is reacted with hydrogen in the presence of a catalyst to produce a mixture of products. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the apparatus used in Example 1 for converting 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) into 1,1,2-trifluoroethane (HFC-143).

[0019] Figure 2 The graph shows the overall selectivity of the 0.2% Pd / α Al2O3 catalyst for the “HFC-143+ recyclable” as a function of catalyst concentration and temperature for the experiment in Example 2.

[0020] Figure 3 This is a graph showing the selectivity % for undesirable byproducts as a function of the phase of the alumina support in the experiment of Example 4, within the range of 200°C-210°C.

[0021] Figure 4 This is a graph showing the substrate conversion of the Pd / Al2O3 catalyst with α, θ, and δ alumina supports for the experiments in Example 4.

[0022] Figure 5 The graph shows the percentage conversion of the 0.2% Pd / α Al2O3 catalyst to the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) substrate as a function of contact time for the experiments in Example 5 at three different temperatures.

[0023] Figure 6 This is a graph showing the product selectivity as a function of temperature for the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using a 0.2% Pd / αAl2O3 catalyst in the experiment of Example 5.

[0024] Figure 7 The graph shows the product selectivity of HFC-143, HCFC-123a, and HCFC-133b as a function of temperature during the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using a 0.2% Pd / α Al2O3 catalyst in the experiment of Example 5. Detailed Implementation

[0025] I. Definition

[0026] As used herein, the singular forms “an,” “a,” and “the” include the plural, unless the context clearly indicates otherwise. Furthermore, when quantities, concentrations, or other values ​​or parameters are given as ranges, preferred ranges, or lists of upper and lower preferred values, it should be understood that all ranges formed by any pair of any upper or lower range or preferred value are specifically disclosed, regardless of whether such ranges are disclosed individually. When ranges of numerical values ​​are listed herein, unless otherwise specified, the range is intended to include its endpoints as well as all integers and fractions within that range. When ranges are defined, it is not intended to limit the scope of this disclosure to the specific values ​​listed.

[0027] As used in this article, the phrase “any range of any two values ​​that are end values ​​among these values” literally means any range that can be selected from any two values ​​listed before such a phrase, regardless of whether those values ​​are in the lower or higher parts of the list. For example, a pair of values ​​can be selected from two lower values, two higher values, or a lower value and a higher value.

[0028] As used herein, the names of refrigerants, including ASHRAE designations (such as “R-143”), IUPAC names “1,1,2-trifluoroethane”, and model abbreviations (such as “HFC-143”), are all used interchangeably to refer to the same refrigerant.

[0029] As used in this article, catalytic materials refer to metal catalysts and any catalyst support materials used in conjunction with metal catalysts.

[0030] As used in this article, catalyst dilution refers to the method of reducing the concentration of a catalyst in a chemical reaction by combining a catalytic material with a diluent substance that is inert or does not catalyze the reaction.

[0031] II. Overview

[0032] This disclosure generally relates to a method for producing E-1,2-difluoroethylene (HFO-1132E) from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) according to a three-step process (“Method 1”) as shown below, the method comprising the following three steps: (i) hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to produce 1,1,2-trifluoroethane (HF) (i) Dehydrofluorination of 1,1,2-trifluoroethane (HFC-143) to produce a mixture of trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z); and (iii) Isomerization of cis-1,2-difluoroethylene (HFO-1132Z) to trans-1,2-difluoroethylene (HFO-1132E).

[0033] The schematic equations for the three steps of Method 1 are shown below:

[0034] Method 1

[0035]

[0036]

[0037]

[0038] The heat of reaction for step (i) was calculated using the DFT (density functional theory) method. The ΔH was -59.7 kcal / mol. f This indicates that step (i) is a strongly exothermic reaction step.

[0039] It has been found that the first step involving the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) can be improved by employing methods for controlling the significant exothermic reaction. In the first method, the hydrogenation catalyst can be diluted to manage the heat generated by the reaction and the reaction rate. In the second method, the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) reactants can be diluted with a certain amount of feedstock diluent before or during the reaction. The aforementioned dilution methods allow for better control of the exothermic reaction in step (i) and minimize catalyst deactivation and the formation of undesirable byproducts. Details of catalyst dilution, feedstock dilution, and related conditions are provided in Section III below.

[0040] Further details regarding each of steps (i), (ii), and (iii) are provided below.

[0041] III. Step (i)

[0042] Step (i) of the method for producing 1,2-difluoroethylene (HFO-1132) involves hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to produce 1,1,2-trifluoroethane (HFC-143). While catalysis can enhance reaction rates and overall efficiency, the exothermic nature of the hydrogenation reaction itself can lead to several drawbacks. It has been found that the high temperatures involved in the hydrogenation reaction in step (i) can lead to catalyst deactivation and a rapid loss of catalyst activity. Furthermore, the increased heat and energy in the reaction environment can promote undesirable side reactions. Each of these factors can potentially reduce the selectivity for the desired product, 1,1,2-trifluoroethane (HFC-143).

[0043] To overcome these challenges, this disclosure provides a catalyst and feedstock dilution method for improving product selectivity in the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143).

[0044] A. Catalyst dilution

[0045] The method of this invention can be used to control reaction rates and prevent excessive catalytic deactivation. By diluting the catalyst, the reaction rate can be carefully tuned to prevent the formation of unwanted byproducts and to enhance catalyst lifetime.

[0046] (i) catalyst

[0047] Catalysts and diluents play important roles in the reaction. Specifically, in the hydrogenation step, the catalytic material may include catalytic metals such as palladium, platinum, rhodium, ruthenium, iron, cobalt, or nickel.

[0048] Catalytic metals can be supported on supports such as activated carbon, porous aluminosilicates (calcium zeolite), alumina, silica, titanium dioxide, zirconium oxide, zinc oxide, and aluminum fluoride. The alumina can be α-alumina, δ-alumina, θ-alumina, or γ-alumina. Supported catalysts can be prepared by impregnating any suitable support with a solution of a compound containing the desired metal composition. The support can also be in the form of spherical agents. After the impregnation step, the solvent can be removed using heat or under vacuum to obtain a solid material, which can be further dried, calcined, and reduced to form the active metal catalyst.

[0049] The catalytic material may include a catalytic metal supported on a support, wherein the amount of the catalytic metal is as low as about 0.01 wt%, about 0.05 wt%, about 0.1 wt%, about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, or as high as about 0.5 wt%, about 0.6 wt%, about 0.7 wt%, about 0.8 wt%, about 0.9 wt%, about 1 wt%, about 1.5 wt%, about 2 wt%, about 5 wt%, about 10 wt%, about 20 wt%, about 30 wt%, about 40 wt%, about 50 wt%, or any range covered by any two of the aforementioned values ​​as end values. For supported noble metal catalysts (such as Pd and Pt), the metal loading may range from about 0.01 wt% to about 5 wt%, preferably from about 0.05 wt% to about 2 wt%, and more preferably from about 0.1 wt% to about 1 wt%.

[0050] When using a palladium catalyst, the palladium loading on the support (such as an α-alumina support) can be from about 0.01 wt% to about 5 wt%, preferably from about 0.05 wt% to about 2 wt%, and more preferably from about 0.1 wt% to about 1 wt%.

[0051] The catalyst used in step (i) can have an appropriate BET (Brunauer, Emmett, and Teller) surface area. In some embodiments, the BET surface area of ​​the catalyst can be as low as about 1 m². 2 / g, approximately 3m 2 / g, approximately 5m 2 / g, approximately 10m 2 / g, approximately 15m 2 / g, approximately 20m 2 / g2 Approximately 30m 2 / g, approximately 40m 2 / g, approximately 50m 2 / g, approximately 100m 2 / g, approximately 200m 2 / g, or up to about 250m 2 / g, approximately 300m 2 / g, approximately 400m 2 / g, approximately 500m 2 / g, approximately 600m 2 / g, approximately 700m 2 / gm 2 Approximately 800m 2 / g, approximately 900m 2 / g, approximately 1000m 2 / g, approximately 2000m 2 / g, or any range covered by any value with the foregoing values ​​as endpoints. For alumina-supported metal catalysts, the BET surface area can be approximately 1 m². 2 / g to approximately 500m 2 / g, preferably about 1m 2 / g to approximately 200m 2 / g, more preferably about 1m 2 / g to approximately 100m 2 / g, and most preferably about 1m 2 / g to approximately 20m 2 / g. BET analysis is a standard method for determining surface area using nitrogen adsorption isotherms. The BET surface area of ​​the catalyst can be measured using a TriStar II Micromeritics instrument. The catalyst sample is degassed before analysis using a FlowPrep 060 instrument.

[0052] When a palladium catalyst is used on an α-alumina support, the BET surface area can be approximately 1 m². 2 / g to approximately 500m 2 / g, preferably about 1m 2 / g to approximately 200m 2 / g, more preferably about 1m 2 / g to approximately 100m 2 / g, and most preferably about 1m 2 / g to approximately 20m 2 / g.

[0053] (ii) Catalyst pretreatment

[0054] Catalysts can be pretreated in various ways to improve their performance and efficiency in reactions. For example, catalysts can be dried at elevated temperatures, ranging from approximately 200°C, 250°C, 300°C, 350°C, 360°C, or 370°C, to approximately 380°C, 390°C, 400°C, 450°C, 500°C, 600°C, or 700°C, or any range encompassed by either of the aforementioned values ​​as end values. As part of the catalyst pretreatment, the catalyst can be exposed to an inert gas (such as N2). The pretreatment process can take as little as approximately 1 hour, 2 hours, or 3 hours, or as long as approximately 4 hours, 5 hours, 6 hours, 10 hours, or 20 hours, or any range encompassed by either of the aforementioned values ​​as end values, such as, for example, approximately 2 hours to approximately 4 hours.

[0055] When a palladium catalyst is used on an α-alumina support, the catalyst can be dried at a temperature of about 200°C to about 700°C, preferably about 200°C to about 500°C, and most preferably about 200°C to about 300°C.

[0056] When a palladium catalyst is used on an α-alumina support, the catalyst can be exposed to an inert gas (such as N2) for about 1 hour to about 20 hours, preferably about 1 hour to about 10 hours, and most preferably about 1 hour to about 3 hours.

[0057] (iii) Catalyst composition

[0058] This disclosure also includes catalyst compositions, such as those used in the diluted catalyst hydrogenation methods described herein.

[0059] In one embodiment, the catalyst composition comprises a palladium metal catalyst for hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reacting with hydrogen to produce 1,1,2-trifluoroethane (HFC-143), the catalyst comprising a catalytic material comprising 0.1 wt% to 1.0 wt% palladium metal supported on an alumina (Al2O3) support (preferably an α-alumina support) based on the total weight of the catalytic metal and the support; and a diluent material, wherein the amount of the catalytic material is from about 5 vol% to about 70 vol% based on the total volume of the catalytic material and the diluent material.

[0060] The diluent material may comprise an inert substance that is not reactive in the reaction of step (i), such as a metal, metal alloy, metal mesh, glass beads, inert α-alumina, or carbon black. The metal mesh material may be made of stainless steel or nickel alloys (such as Monel, Inconel, etc.). These meshes have a relatively large surface area and provide physical support for the catalyst, thereby allowing the reaction mixture to flow through while reducing the catalyst concentration.

[0061] Diluent materials can be combined with catalytic materials through solid mixing techniques, such as simple solid mixing or shaking, to uniformly combine and distribute the catalytic materials and diluent materials.

[0062] The diluent material can be present in such an amount that, based on the total volume of the catalyst material and the diluent material, the amount of the catalyst material can be as low as about 5% by volume, about 10% by volume, about 15% by volume, about 20% by volume, about 25% by volume, or as high as about 30% by volume, about 35% by volume, about 40% by volume, about 45% by volume, about 50% by volume, about 55% by volume, about 60% by volume, about 65% by volume, about 70% by volume, or within any range covered by any two of the aforementioned values ​​as end values. For example, based on the total volume of the catalyst material and the diluent material, the amount of the catalyst material can be about 5% by volume to about 70% by volume, about 10% by volume to about 50% by volume, or about 10% by volume to about 30% by volume.

[0063] The hydrogenation reaction in step (i) can be carried out in a suitable reactor in the gas or vapor phase, such as a tubular reactor made of a temperature- and / or corrosion-resistant material, such as nickel and its alloys, including Hastelloy (e.g., Hastelloy C276), Incoloy (e.g., Incoloy 600), Incoloy and Monel, and the container can be lined with a fluoropolymer.

[0064] The reactor can first be cleaned and flushed with an inert gas (such as nitrogen), and then filled with a catalyst (such as those described below). The catalyst can be pretreated in the reactor, such as by drying as further described below, before the reactants are metered into the reactor to start the reaction.

[0065] The process flow can pass through the catalyst bed in a downward or upward direction. Products can flow through one or more scrubbers to remove byproducts such as hydrogen fluoride (HF) and / or hydrogen chloride (HCl) from the reaction, and reaction products can be collected, for example, by trapping in a cooled cylinder.

[0066] B. Raw material dilution

[0067] To reduce the heat of the reaction, prevent excessive catalytic deactivation, and / or minimize the formation of undesirable byproducts, the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) feedstock can be diluted with a feedstock diluent (such as an inert gas) or one or more non-reactive organic molecules, each of which does not participate in the subsequent reaction. In the case of feedstock dilution, an undiluted catalyst can be used, or a diluted catalyst can be used as described above.

[0068] Suitable inert gases include nitrogen and argon.

[0069] Non-reactive organic molecules that can be used as feedstock diluents may include internal feedstock diluents, which are organic molecules that are generated in the reaction of step (i) and then optionally separated from other products and recycled or otherwise reintroduced into the reaction of step (i) by combination with 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) feedstock.

[0070] For example, suitable nonreactive organic molecules include 1,1,2-trifluoroethane (HFC-143), which is the target product of step (i) and can be separated from the product mixture of step (i) before being combined with the starting material 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). Alternatively, a diluent for the 1,1,2-trifluoroethane (HFC-143) starting material can be introduced independently from sources other than the product of step (i).

[0071] Other non-reactive organic molecules that can be used as raw material diluents may include external raw material diluents, which are organic molecules that are not generated in step (i) but are introduced into step (i) from an external source by combination with 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) raw material.

[0072] Non-reactive organic molecules that can be used as external raw material diluents may include fluoromethane (HFC-41), difluoromethane (HFC-32), trifluoromethane (HFC-23), 1,1-difluoroethane (HFC-152a), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1,2,2-pentafluoroethane (HFC-125), 1,1,1,2-tetrafluoropropane (HFC-254eb), and 1,1,1,2-tetrafluoropropane (HFC-254e). b) 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,2,2-pentafluoropropane (HFC-245cb), 1,1,1,2,3-pentafluoropropane (HFC-245eb), 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), and combinations thereof.

[0073] The molar ratio of the raw material diluent to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) can be in the range of 0.25 / 1 to 10 / 1, preferably 0.5 / 1 to 8 / 1, and more preferably 1 / 1 to 4 / 1.

[0074] C. Step (i) reaction

[0075] Figure 1 An embodiment of a reactor apparatus suitable for the reaction in step (i) is provided. Referring to the process flow diagram 100 shown therein, a source of N2, acting as an inert carrier, is supplied from cylinder 102, and a source of H2 is supplied from cylinder 104. An organic feedstock comprising 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is supplied from cylinder 106. Cylinders 102, 104, and 106 are all connected to a KOH scrubber 108, which is coupled to a vent 110. The sources of N2, H2, and the organic feedstock are fed into reactor 112, which is surrounded by a box oven 114. The reaction can be monitored by sampling from outlet 120 and performing GC analysis.

[0076] As the reaction proceeds, the product is fed into a storage tank 116, which is immersed in a dry ice bath or a dry ice and acetone mixture bath 118. The dry ice or dry ice and acetone mixture bath is configured to maintain the temperature of the storage tank 116 at approximately -87°C. The storage tank 116 is connected to a buffer beating tank 112 to prevent potential backflow of the KOH solution, which is also connected to a KOH scrubber 124. The scrubber 124 has a vent 126 open to the atmosphere. It includes the target product 1,1,2-trifluoroethane (HFC-143), recyclable byproducts (such as 1-chloro-1,1,2-trifluoroethane (HCFC-133b) and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a)), acids (such as HCl and HF), and non-recyclable byproducts (such as 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1 The materials of 1-difluoroethylene (HFO-1132a), 1-chloro-1,1-difluoroethane (HCFC-142b), 1-chloro-1,2-difluoroethane (HCFC-142a), and chloroethane (HCC-160), as well as the unconverted raw material 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) collected in storage tank 116, can undergo multiple purification steps (such as acid removal, drying, and distillation) to separate the HFC-143 product. A portion of the purified HFC-143 can be co-fed as a diluent into the reactor of step (I).

[0077] The reaction temperature can be as low as about 100°C, about 150°C, about 200°C, about 210°C, about 220°C, about 230°C, about 240°C, about 250°C, about 260°C, about 270°C, about 280°C, about 290°C, or as high as about 300°C, about 350°C, about 400°C, or any range covered by two values ​​that are the endpoints of the foregoing values, for example, about 100°C to about 300°C or preferably about 150°C to about 250°C.

[0078] When a palladium catalyst is used on an α-alumina support, the reaction temperature can be from about 100°C to about 400°C, preferably from about 100°C to about 300°C, and most preferably from about 150°C to about 250°C.

[0079] The contact time between the reactants and the catalyst can be as short as about 0.1 seconds, about 1 second, about 5 seconds, about 10 seconds, about 15 seconds, or about 20 seconds, or as long as about 25 seconds, about 30 seconds, about 40 seconds, about 50 seconds, about 60 seconds, or about 120 seconds, or any range covered by the two values ​​that are the extreme values ​​mentioned above. For example, the contact time can preferably be from about 1 second to about 60 seconds.

[0080] When a palladium catalyst is used on an α-alumina support, the contact time can be from about 1 second to about 60 seconds, preferably from about 5 seconds to about 40 seconds, and most preferably from about 10 seconds to about 30 seconds.

[0081] The pressure can be as low as about 1 psig, about 3 psig, about 5 psig, about 10 psig, about 15 psig, about 20 psig, about 30 psig, about 35 psig, or about 40 psig, or as high as about 50 psig, about 60 psig, about 70 psig, about 80 psig, about 90 psig, about 100 psig, about 120 psig, about 150 psig, about 200 psig, about 250 psig, or about 300 psig, or any range covered by the two values ​​that are the extreme values ​​mentioned above. For example, the pressure can preferably be from about 10 psig to about 100 psig.

[0082] When a palladium catalyst is used on an α-alumina support, the pressure can be from about 1 psig to about 300 psig, preferably from about 1 psig to about 200 psig, and most preferably from about 10 psig to about 100 psig.

[0083] The molar ratio of hydrogen to CFC-113 reactant can be as small as about 2:1, about 3:1, about 4:1, about 5:1, about 5.5:1, or as large as about 6:1, about 6.5:1, about 7.5:1, about 8:1, about 12:1, about 15:1, or about 20:1, or within any range covered by the two values ​​that are the end values ​​of the foregoing. The molar ratio of hydrogen to CFC-113 can preferably be from 3:1 to 15:1, and more preferably from 4:1 to 10:1.

[0084] When a palladium catalyst is used on an α-alumina support, the molar ratio of hydrogen to CFC-113 reactants can be from about 2:1 to about 20:1, preferably from 3:1 to 15:1, and most preferably from 4:1 to 10:1.

[0085] As demonstrated by the examples herein, the hydrogenation step, for example, can achieve selectivity for the 1,1,2-trifluoroethane (HFC-143) product from as low as about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70% to as high as about 75%, about 80%, about 90% or more, or within any range covered by the two values ​​that are the endpoints of the foregoing values.

[0086] When a palladium catalyst is used on an α-alumina support, the hydrogenation step can achieve a selectivity of about 10% to about 70% for the 1,1,2-trifluoroethane (HFC-143) product, preferably about 10% to about 50%, and most preferably about 20% to about 40%.

[0087] Hydrogenation can also produce several intermediates, such as 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123). These intermediates are recyclable and can eventually be converted into 1,1,2-trifluoroethane (HFC-143). As demonstrated by the embodiments herein, the hydrogenation step can achieve a combination selectivity for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) greater than about 30%, greater than about 40%, greater than about 50%, greater than about 60%, greater than about 70%, greater than about 80%, greater than about 90%, greater than about 95%, or within any range covered by two values ​​that are endpoints of the foregoing values.

[0088] When a palladium catalyst is used on an α-alumina support, the hydrogenation step can achieve a combined selectivity and / or selectivity of more than about 30% for each of 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), preferably more than about 40%, and most preferably more than about 50%. Hydrogenation can also produce several byproducts, such as 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethylene (HFO-1132a), 1-chloro-1,1-difluoroethane (HCFC-142b), 1-chloro-1,2-difluoroethane (HCFC-142a), and chloroethane (HCC-160), which are the result of the defluorination side reaction. These byproducts are undesirable because they are difficult to recycle or convert back to 1,1,2-trifluoroethane (HFC-143). As demonstrated by the examples herein, the hydrogenation step can achieve a combination selectivity of less than about 30%, less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 9%, less than about 8%, less than about 7%, less than about 6%, less than about 5%, or within any range covered by the two values ​​that are the endpoints of the foregoing values.

[0089] When a palladium catalyst is used on an α-alumina support, the hydrogenation step can achieve a combined selectivity and / or selectivity of less than about 30% for each of 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1-chloro-1,2-difluoroethane (HCFC-142a), and chloroethane (HCC-160), preferably less than about 25%, and most preferably less than about 20%.

[0090] As demonstrated by the examples herein, the hydrogenation step, for example, can achieve conversions from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) ranging from as little as about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, or about 75% to as much as about 90%, about 95%, about 97%, about 98%, about 99%, or greater, or within any range covered by the two values ​​that are the endpoints of the foregoing values.

[0091] When a palladium catalyst is used on an α-alumina support, the hydrogenation step can achieve a conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) greater than about 10%, preferably greater than about 20%, and most preferably greater than about 30%.

[0092] After prolonged use, periodic regeneration of the catalyst can also be advantageous while it remains in place within the reactor. Catalyst regeneration can be achieved by any method known in the art (e.g., by passing air or nitrogen-diluted air through the catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 375°C, for about 0.5 hours to about 3 days). This can be followed by hydrogen treatment of the carbon and alumina-supported metal catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C.

[0093] When a palladium catalyst is used on an α-alumina support, one or more of the following properties may be present: The reaction temperature can be from about 100°C to about 400°C, preferably from about 100°C to about 300°C, and most preferably from about 150°C to about 250°C. The contact time can be from about 1 second to about 60 seconds, preferably from about 5 seconds to about 40 seconds, and most preferably from about 10 seconds to about 30 seconds. The pressure can be from about 1 psig to about 300 psig, preferably from about 1 psig to about 200 psig, and most preferably from about 10 psig to about 100 psig. The molar ratio of hydrogen to CFC-113 reactants can be from about 2:1 to about 20:1, preferably from 3:1 to 15:1, and most preferably from 4:1 to 10:1. The hydrogenation step can achieve a selectivity of about 10% to about 70% for the 1,1,2-trifluoroethane (HFC-143) product, preferably from about 10% to about 50%, and most preferably from about 20% to about 40%. The hydrogenation step can achieve a combined selectivity and / or selectivity of more than about 30% for each of 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), preferably more than about 40%, and most preferably more than about 50%. The hydrogenation step can achieve a combined selectivity and / or selectivity of less than about 30% for each of 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1-chloro-1,2-difluoroethane (HCFC-142a), and chloroethane (HCC-160), preferably less than about 25%, and most preferably less than about 20%. The hydrogenation step can achieve a conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) greater than about 10%, preferably greater than about 20%, and most preferably greater than about 30%.

[0094] D. Combining catalyst dilution with feedstock dilution

[0095] In the hydrogenation reaction of step (i), as described above and in the examples below, the techniques for catalyst dilution and feedstock dilution can be combined, i.e., they can be used simultaneously or in combination with each other.

[0096] IV. Step (ii)

[0097] The defluorination reaction in step (ii) can be carried out in a suitable reactor in the gas or vapor phase, such as a tubular reactor made of a material resistant to temperature and / or corrosion, such as nickel and its alloys, including Hastelloy (e.g., Hastelloy C276), Incol (e.g., Incol 600), Incoloy alloys and Monel alloys, wherein the container may be lined with a fluoropolymer.

[0098] The reactor can first be cleaned and flushed with an inert gas (such as nitrogen), and then filled with a catalyst (such as those described below). The catalyst can be pretreated in the reactor, such as by drying as further described below, before the reactants are metered into the reactor to start the reaction.

[0099] The process flow can pass through the catalyst bed in a downward or upward direction. Reactants can flow through a scrubber to remove byproducts such as hydrogen fluoride (HF) and / or hydrogen chloride (HCl) from the reaction, and reaction products can be collected, for example, by trapping in a cooled cylinder.

[0100] Catalysts and process conditions play an important role in the defluorination reaction.

[0101] Suitable catalysts for the defluorination reaction include metal oxides such as chromium oxide, aluminum oxide, iron oxide, and magnesium oxide. Fluorination of the catalyst can be carried out using anhydrous HF under conditions that efficiently convert a portion of the metal oxide into the corresponding metal fluoride, such as via the process disclosed in U.S. Patent No. 6,780,815 to Cerri et al., the disclosure of which is expressly incorporated herein by reference. Other suitable catalysts for the defluorination reaction include metal fluorides such as chromium fluoride, aluminum oxide fluoride, iron fluoride, magnesium fluoride, and various combinations thereof.

[0102] Other metals, such as Pd and Ni, can also be loaded onto the aforementioned fluorinated metal oxides, for example, via a wet impregnation method, wherein the metal salt is exposed to the fluorinated metal oxide support in solution, followed by drying, calcination, and subsequent reduction with hydrogen.

[0103] Based on the total weight of the catalyst and the support, the amount of metal supported on the support can be about 0.01 wt%, about 0.05 wt%, about 0.1 wt%, about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%, or about 1 wt% to about 2 wt%, about 3 wt%, 5 wt%, 10 wt%, or 20 wt%, or 30 wt%, or 40 wt%, or 50 wt%, or any range covered by the two values ​​that are the end values ​​of the foregoing. For supported noble metal (Pd, Pt, etc.) catalysts, the metal loading can be in the range of 0.01 wt% to 5 wt%, preferably 0.05 wt% to 2 wt%, more preferably 0.1 wt% to 1 wt%.

[0104] The catalyst used in step (ii) can have an appropriate BET (Brunauer, Emmett, and Teller) surface area. In some embodiments, the BET surface area of ​​the catalyst can be as low as 10 m². 2 / g、20m 2 / g、30m 2 / g、40m 2 / g, 50m 2 / g、60m 2 / g、70m 2 / g、80m 2 / g、90m 2 / g, 100m 2 / g or up to 110m 2 / g、120m 2 / g、130m 2 / g, 140m 2 / g, 150m 2 / g、175m 2 / g、200m 2 / g、225m 2 / g、250m 2 / g、300m 2 / g, or any range covered by any value with the foregoing values ​​as endpoints. For metal oxide catalysts, the BET surface area can preferably be greater than 100 m². 2 / g. For fluorinated metal oxide catalysts, the BET surface area can preferably be greater than 20m². 2 / g. BET analysis is a standard method for determining surface area using nitrogen adsorption isotherms. The BET surface area of ​​the catalyst can be measured using a TriStar II Micromeritics instrument. The catalyst sample is degassed before analysis using a FlowPrep 060 instrument.

[0105] The catalyst can be pretreated by drying at elevated temperatures, ranging from approximately 200°C, 250°C, 300°C, 350°C, 360°C, or 370°C, to approximately 380°C, 390°C, 400°C, 450°C, or 500°C, or any range encompassed by either of the aforementioned values ​​as end values. As part of the catalyst pretreatment, the catalyst can be exposed to an inert gas (such as N2). The pretreatment process can take from approximately 1 hour, 2 hours, or 3 hours, to approximately 4 hours, 5 hours, 6 hours, 10 hours, or 20 hours, or any range encompassed by either of the aforementioned values ​​as end values, such as, for example, approximately 2 hours to approximately 4 hours.

[0106] The temperature range for the defluorination reaction can be as low as about 150°C, about 200°C, about 250°C, about 300°C, about 350°C, about 400°C, about 450°C, or as high as about 500°C, about 550°C, about 600°C, about 650°C, about 700°C, about 750°C, about 800°C, or any range covered by two values ​​that are endpoints of the foregoing values. The temperature can preferably be from about 250°C to about 450°C, and more preferably from about 300°C to about 400°C.

[0107] The pressure can be as low as about 1 psig, about 2 psig, about 3 psig, about 4 psig, or about 5 psig, about 10 psig, about 15 psig, about 20 psig, about 25 psig, about 30 psig, about 35 psig, about 40 psig, about 50 psig, or any range covered by two values ​​that are the endpoints of the foregoing values. For example, the pressure can be from about 1 psig to about 50 psig, preferably from about 5 psig to about 30 psig, and more preferably from about 10 psig to about 20 psig.

[0108] The contact time between the reactants and the catalyst can be as low as about 0.1 seconds, about 1 second, about 5 seconds, about 10 seconds, about 15 seconds, or about 20 seconds, or as long as about 25 seconds, about 30 seconds, about 40 seconds, about 50 seconds, about 60 seconds, or about 120 seconds, approximately or within any range covered by the two values ​​that are the extreme values ​​mentioned above. For example, the contact time can be from about 1 second to about 60 seconds.

[0109] In the defluorination reaction of step (ii), the cis / trans molar ratio of 1,2-difluoroethylene in the product mixture can be as low as about 1, about 2, about 3, about 4, about 5, about 6, or as high as about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, or any range covered by the two values ​​that are the endpoints of the foregoing values. For example, the cis / trans ratio can be from about 2 to about 15.

[0110] The selectivity for the desired 1,2-difluoroethylene products (the sum of 1232E and 1232Z) can be as low as about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, or as high as about 96%, about 97%, about 98%, about 99%, or any range covered by the two values ​​that are the endpoints of the foregoing values. For example, the selectivity can be from about 89% to about 99%.

[0111] The conversion of the starting material to 1,2-difluoroethylene can be as low as about 10%, about 20%, about 30%, about 40%, or as high as about 50%, about 60%, about 70%, about 80%, about 90%, about 95%, about 99%, or any range covered by the two values ​​that are the end values ​​of the foregoing.

[0112] After prolonged use, periodic regeneration of the catalyst can also be advantageous while it remains in place in the reactor. Catalyst regeneration can be achieved by any method known in the art (e.g., by passing air or nitrogen-diluted air through the catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 375°C, for about 0.5 hours to about 3 days). This can be followed by hydrogen fluoride treatment of the fluorinated catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C, or hydrogen treatment of the supported transition metal catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C.

[0113] During the reaction, byproducts formed in step (i) and / or step (ii), such as HCFC-133b, HCFC-1133, HCFC-123a, and HFO-1123, can be recycled back to the reactor inlet as needed.

[0114] In addition, this method advantageously avoids and / or minimizes the formation of 1,1,1-trifluoroethane (HFC-143a), wherein the product of step (ii) (including trans-1,2-difluoroethylene (HFO-1132E)) may include less than 5% by weight, less than 3% by weight, less than 1% by weight, less than 0.5% by weight, or less than 0.1% by weight of 1,1,1-trifluoroethane (HFC-143a) based on the total weight of the product composition.

[0115] V. Step (iii)

[0116] The 1,2-difluoroethylene (HFO-1132) obtained in step (ii) above can be produced as a mixture containing both the trans-1,2-difluoroethylene (HFO-1132E) isomer and the cis-1,2-difluoroethylene (HFO-1132Z) isomer.

[0117] In step (iii), the cis-1,2-difluoroethylene (HFO-1132Z) isomer can be converted to the trans-1,2-difluoroethylene (HFO-1132E) isomer by exposure to heat and / or a catalyst, thereby producing a final product comprising, constituting, or composed of, a high-purity trans-1,2-difluoroethylene (HFO-1132E) isomer, wherein the high purity is such as at least about 95% by weight, at least about 99.0% by weight, at least about 99.9% by weight, at least about 99.99% by weight, or greater.

[0118] The isomerization reaction can be carried out in any suitable reaction vessel or reactor, but should preferably be constructed of corrosion-resistant materials such as nickel and its alloys, including Hastelloy (e.g., Hastelloy C276), Incoloy (e.g., Incoloy 600), Incoloy alloys, and Monel alloys, wherein the vessel may be lined with a fluoropolymer. These can be single-tube or multi-tube reactors filled with an isomerization catalyst.

[0119] The temperature range for the isomerization reaction can be as low as about 100°C, about 150°C, about 200°C, about 250°C, about 300°C, about 350°C, about 400°C, about 450°C, or as high as about 500°C, about 550°C, about 600°C, about 650°C, about 700°C, about 750°C, about 800°C, or any range covered by two values ​​that are the endpoints of the foregoing values.

[0120] The reaction can be carried out at atmospheric pressure, extra-atmospheric pressure, or vacuum. Vacuum pressure can be from about 5 Torr to about 760 Torr. The contact time between the reactants and the catalyst can range from about 0.5 seconds to about 120 seconds, however, longer or shorter times are also possible.

[0121] VI. Reaction Products

[0122] The multi-step reaction described in Parts I-V can produce a composition containing relatively high purity trans-1,2-difluoroethylene (HFO-1132E).

[0123] In one embodiment, the composition may comprise, based on the total weight of the composition, at least 95% by weight of trans-1,2-difluoroethylene (HFO-1132E); and less than 5% by weight of 1,1,1-trifluoroethane (HFC-143a).

[0124] In another embodiment, the composition may comprise, based on the total weight of the composition, at least 97% by weight of trans-1,2-difluoroethylene (HFO-1132E); and at less than 3% by weight of 1,1,1-trifluoroethane (HFC-143a).

[0125] In another embodiment, the composition may comprise, based on the total weight of the composition, at least 99% by weight of trans-1,2-difluoroethylene (HFO-1132E); and at less than 1% by weight of 1,1,1-trifluoroethane (HFC-143a).

[0126] It should be understood that the above description is merely illustrative of this disclosure. Various alternatives and modifications can be devised by those skilled in the art without departing from this disclosure. Therefore, this disclosure is intended to cover all such alternatives, modifications, and variations that fall within the scope of the appended claims.

[0127] Example

[0128] Example 1

[0129] Catalyst dilution study

[0130] This example demonstrates the beneficial effect of catalyst dilution in improving product selectivity when using Pd / Al₂O₃ as a catalyst to convert 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143). The experimental apparatus used in this example is... Figure 1 The setup includes a feed system containing gas flow controllers for N2 and H2 and a micro-motion mass flow meter connected to a research control valve (RCV) that controls the flow rate of the organic stream. The reactor consists of a one-inch SS tube filled with catalyst. A thermocouple is inserted into the middle of the catalyst bed to read the operating temperature. The pressure control system consists of an RCV that controls the pressure by receiving feedback from a pressure transducer placed after the reactor. For GC analysis, the sample is removed after the reactor using a sample bag filled with 50 ml of water to capture HCl and HF. Prior to GC analysis, the sample bag is heated at 60°C for one hour to ensure all organic contents are in the gas phase. The sample is then removed using a syringe and injected into the GC instrument for analysis.

[0131] In the first embodiment, 0.5% Pd / θ-Al2O3 catalyst was diluted with 40 ml of 1 / 8'' SS mesh packing material and then loaded into the reactor. The catalyst was pretreated with H2 at 200°C for one hour. Then, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) was introduced into the reactor at a flow rate of 10 g / h while H2 was passed through the catalyst bed at 200°C at a flow rate of 150 ml / min. The catalyst bed temperature was raised to 216°C upon introduction of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). As shown in Table 1, the conversion was 73.33%, and the selectivity for "R-143+ recyclables" was 83.00%. The total selectivity for undesirable byproducts was 17.00%. More specifically, the selectivity of R-142a was 6.27%, that of ethane was 4.23%, that of R-160 was 2.32%, that of R-143a was 1.00%, and that of R-152a was 0.42%.

[0132] In each of the tables below, the product / intermediate may contain additional recyclable components, such as 1-chloro-1,1,2-trifluoroethane (HCFC-133b) and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), as well as trifluoroethylene (HFO-1123). These intermediates are recyclable and can ultimately be converted to 1,1,2-trifluoroethane (HFC-143). Reference Figure 1 The process flow shown allows these recyclable components to be fed back into reactor 112 from collection tank 116 via line 128 for further reaction.

[0133] In each of the tables below, byproducts may include 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethylene (HFO-1132a), 1-chloro-1,2-difluoroethane (HCFC-142a), 1-chloro-1,1-difluoroethane (HCFC-142b), and chloroethane (HCC-160). These byproducts are the result of the defluorination side reaction and are difficult to recycle or convert back to 1,1,2-trifluoroethane (HFC-143).

[0134] Table 1

[0135] Product distribution of 0.5% Pd / θ Al2O3 catalyst before and after dilution

[0136]

[0137] In Table 1, the H2 flow rate was 10 ml / min, the I13 flow rate was 10 g / h, and the pressure was 45 psig. For dilution, 10 ml of 0.5% Pd / θ Al2O3 catalyst was diluted with 40 ml of 1 / 8'' SS mesh packing material.

[0138] Figure 1 This is a schematic diagram of the apparatus used in Example 1 for converting 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) into 1,1,2-trifluoroethane (HFC-143).

[0139] Comparative Example 1

[0140] Studies on reactions using undiluted catalysts

[0141] This example demonstrates the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using undiluted Pd / Al₂O₃. The reaction and product analysis were performed using the same apparatus and procedures described in Example 1. 50 mL of 0.5% Pd / θAl₂O₃ catalyst was loaded into a tubular reactor and pretreated with H₂ at 200 °C for one hour. Then, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) was introduced into the reactor at a flow rate of 10 g / h while H₂ was passed through the catalyst bed at 200 °C at a rate of 150 mL / min. The catalyst bed temperature was raised to 225 °C upon introduction of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). As shown in Table 1, the conversion rate was 98.76%, and the selectivity for “R-143+ recyclable” was 58.34%. The total selectivity for undesirable byproducts was 41.66%. More specifically, the selectivity for R-142a was 16.65%, for ethane 12.74%, for R-160 5.73%, for R-143a 1.61%, and for R-152a 0.03%. This indicates that the Pd / θAl2O3 catalyst, when used undiluted, exhibits high activity for undesirable hydrogenation-defluorination side reactions.

[0142] Example 2

[0143] Effect of catalyst dilution on the selectivity of desired products and / or recyclables

[0144] This example demonstrates that when the catalyst concentration is less than 50%, maximum selectivity for the 143+ recyclable material is achieved in the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using a Pd / α Al2O3 catalyst. Catalyst concentration is expressed as a volume percentage of the catalyst relative to the total volume of the catalyst bed. Generally, the total volume of the catalyst bed is 50 ml. In this example, four different catalyst concentrations were considered by mixing 10 ml, 17 ml, 25 ml, and 35 ml of 0.2% Pd / α Al2O3 catalyst with sufficient 1 / 8'' SS mesh packing material to achieve a total volume of 50 ml. The reaction and product analysis were performed using the same apparatus and procedures as in Example 1.

[0145] like Figure 2 As shown, a 70% catalyst concentration resulted in lower overall selectivity for the 143+ recyclable material compared to concentrations below 50%; this was more pronounced when observing data at higher temperatures. The percentages in the figure represent the volume percentage of the catalyst after dilution with inert materials. The H2 flow rate was 10 ml / min, the 113 flow rate was 10 g / h, and the pressure was 45 psig. The data points shown are averages of 2–6 data points collected every two hours.

[0146] Example 3

[0147] Conversion and selectivity of undesirable products using Pd / Al2O3 catalyst

[0148] Example 3 demonstrates that the Pd / Al₂O₃ catalyst exhibits low selectivity for the undesirable byproduct R-152a in the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143). The reaction and product analysis were performed using the same apparatus and procedures described in Example 1. Six different Pd / Al₂O₃ catalysts from different sources were tested. The BET surface area of ​​the catalysts was measured using a TriStar II Micromeritics instrument. Samples were degassed prior to analysis using a FlowPrep 060 instrument. The measured surface area of ​​the 0.1% Pd / γAl₂O₃ catalyst was 301.0 m². 2 The measured surface area of ​​the 0.5% Pd / γ Al2O3 catalyst was 302.8 m² / g. 2 The measured surface area of ​​the 0.3% Pd / δ Al2O3 catalyst was 124.4 m² / g. 2 The measured surface area of ​​the 0.3% Pd / θ Al2O3 catalyst was 40.2 m² / g. 2The measured surface area of ​​the 0.5% Pd / θ Al2O3 catalyst was 41.1 m² / g. 2 / g, and the measured surface area of ​​the 0.2% Pd / α Al2O3 catalyst is 3.9m². 2 / g. Table 2 shows the conversion and selectivity of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) two hours after diluting 10 ml of Pd / Al2O3 catalyst with 40 ml of 1 / 8'' SS mesh packing material. The results indicate that the selectivity for R-152a is preferably in the range of about 0.1% to about 4% over the entire temperature range studied (about 150 °C to about 220 °C).

[0149] Table 2

[0150] Pd / Al2O3 catalyst activity and selectivity

[0151]

[0152] In Table 2, 10 ml of catalyst was diluted with 40 ml of packing material. The H2 flow rate was 10 ml / min, the I13 flow rate was 10 g / h, and the pressure was 45 psig.

[0153] Comparative Example 3

[0154] Comparison of selectivity for desired products between Pd / C catalysts and Pd / Al2O3 catalysts

[0155] Comparative Example 3 demonstrated that, compared to the Pd / Al₂O₃ catalyst (Example 3), the Pd / C catalyst generally exhibited higher selectivity for the undesirable byproduct R-152a in the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143). The reaction and product analysis were performed using the same apparatus and procedures as described in Example 1. Three different Pd / C catalysts with different Pd weight loadings were explored. Table 3 shows the conversion and selectivity of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) when 10 ml of Pd / C catalyst was diluted with 40 ml of 1 / 8'' SS mesh packing material. Throughout the studied temperature range of 150°C to 250°C, the selectivity for R-152a ranged from 5.51% to 11.55%, which is higher than the selectivity observed on Pd / Al2O3 catalysts (Example 3). Furthermore, at approximately 162°C, the maximum observed selectivity for "143+ recyclable" on the Pd / C catalyst was 93.37% for 1% Pd / C catalysts; almost all Pd / Al2O3 catalysts showed higher overall selectivity at similar temperatures.

[0156] Table 3

[0157] Reactivity and product distribution of Pd / C catalysts

[0158]

[0159] Dilute 10 ml of catalyst with 40 ml of packing material. The H2 flow rate is 10 ml / min, the I13 flow rate is 10 g / h, and the pressure is 45 psig.

[0160] Example 4

[0161] Catalyst thermal stability study

[0162] Example 4 demonstrates that the α phase of alumina is the preferred phase for the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using Pd / Al₂O₃ as a catalyst. The reaction and product analysis were performed using the same apparatus and procedures described in Example 1. Six different Pd / Al₂O₃ catalysts from various sources were explored, and the initial conversion / selectivity results after two hours of operation are shown in Table 2. (See Table 2 and...) Figure 3As shown, byproduct formation follows this trend: α < θ < δ < γ. Since support stability follows the opposite trend, it appears that less stable supports are more reactive to the hydrogenation-defluorination reaction.

[0163] Figure 3 The selectivity for undesirable byproducts as a function of the alumina support phase is shown in the temperature range of 200-210°C. The α, θ, and δ alumina catalysts used were 0.2% Pd / α Al₂O₃, 0.3% Pd / θ Al₂O₃, and 0.3% Pd / δ Al₂O₃, respectively. For these experiments, 10 ml of catalyst was diluted with 40 ml of packing material. The H₂ flow rate was 150 ml / min, the I₁₃ flow rate was 10 g / h, and the pressure was 45 psig. Byproducts included R-152a, R-170, R-143a, R-1132a, R-142b, R-142a, and R-160.

[0164] The long-term stability of the catalyst is also affected by the support phase. Catalysts using γ-Al₂O₃ as the support deactivate very rapidly. The conversion percentage of the 0.5% Pd / γ-Al₂O₃ catalyst decreased from 56.91% after two hours to 41.07% after eight hours at 165 °C. The conversion percentage of the 0.1% Pd / γ-Al₂O₃ catalyst decreased from 24.52% after two hours to 19.97% after eight hours at 155 °C. At similar temperatures, the 0.2% Pd / α-Al₂O₃ catalyst showed no signs of deactivation until 250 hours (see Table 4). Figure 4 As shown, the 0.3% Pd / δ Al2O3 catalyst deactivated very rapidly after 6 hours at 206 °C, and the 0.3% Pd / θ Al2O3 catalyst showed an 8% decrease in conversion (from 92% to 84%) over 15 hours at 210 °C. On the other hand, using the 0.2% Pd / α Al2O3 catalyst at 200 °C, the conversion increased from 95.9% to 97.9% during 22 hours of operation.

[0165] Figure 4The catalysts used were 0.2% Pd / α Al₂O₃, 0.3% Pd / θ Al₂O₃, and 0.3% Pd / δ Al₂O₃. The temperature for the 0.2% Pd / α Al₂O₃ catalyst was 200°C, for the 0.3% Pd / θ Al₂O₃ catalyst it was 210°C, and for the Pd / δ Al₂O₃ catalyst it was 205°C. 10 ml of each catalyst was diluted with 40 ml of packing material used for the 0.1% Pd / γ Al₂O₃, 0.5% Pd / γ Al₂O₃, 0.3% Pd / θ Al₂O₃, and 0.3% Pd / δ Al₂O₃ catalysts. 25 ml of the Pd / α Al₂O₃ catalyst was diluted with 25 ml of packing material at 200°C. The H₂ flow rate was 150 ml / min, the I₂ flow rate was 10 g / h, and the pressure was 45 psig.

[0166] The stability of the 0.2% Pd / α Al₂O₃ catalyst was evaluated at 160 °C for 250 hours. The results are summarized in Table 4 below. The initial substrate conversion after two hours at 160 °C was 46.61%, and the selectivity for the “143+ recyclable” was 94.64%, as shown in Table 2. Table 4 shows the performance of the catalyst under the same conditions for 250 hours. GC samples were collected every four hours, and the results were averaged over 50 hours. The conversion and overall selectivity for the “143+ recyclable” increased slowly over time. The selectivity for the unwanted byproduct R-152a decreased over time, while the selectivity for R-170, R-160, and R-142s increased over time; the net effect was the decrease in the overall selectivity for the unwanted byproducts.

[0167] Table 4

[0168] At 160 °C, 0.2% Pd / αAl₂O₃ catalyst was used in the reaction of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to... Long-term performance of 1,1,2-trifluoroethane (HFC-143) during conversion

[0169]

[0170] In Table 4, 10 ml of catalyst was diluted with 40 ml of packing material. The H2 flow rate was 150 ml / min, the I13 flow rate was 10 g / h, and the pressure was 45 psig.

[0171] Example 5

[0172] Conversion of palladium on α-alumina catalyst

[0173] This example demonstrates that optimizing reaction conditions using a 0.2% Pd / αAl₂O₃ catalyst enhances product selectivity for the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143). The reaction and product analysis were performed using the same apparatus and procedures described in Example 1. Table 5 shows the experiments conducted. At a given temperature, substrate conversion increased with increasing contact time. Figure 5 Compared to temperature, contact time has a smaller impact on product selectivity. For example... Figure 6 As shown, considering all the experiments presented in Table 5, the selectivity for 143 and 123a increases with increasing temperature, while the selectivity for 133b decreases with increasing temperature. Additionally, the selectivity for undesirable byproducts increases with increasing temperature. Figure 7 As shown, the net effect is a decrease in the overall selectivity of "143+ recyclables". At temperatures below 160°C, an overall selectivity of over 95% for "143+ recyclables" can be achieved.

[0174] Table 5

[0175] 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) was converted to 1, using a 0.2% Pd / αAl2O3 catalyst. Process conditions, substrate conversion and product selectivity in the production of 1,2-trifluoroethane (HFC-143)

[0176]

[0177] In Table 5, the specified volume of catalyst was diluted with sufficient packing material to make a total volume of 50 ml. All reactions were carried out at 45 psig.

[0178] Figure 5 The percentage conversion of the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) substrate by the 0.2% Pd / α Al₂O₃ catalyst as a function of contact time is shown at three different temperatures. The data correspond to the experiments presented in Table 5.

[0179] Figure 6 The product selectivity as a function of temperature for the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using a 0.2% Pd / αAl2O3 catalyst is shown. The data correspond to the experiments presented in Table 5.

[0180] Figure 7The product selectivity for 143, 123a, and 133b as a function of temperature is shown during the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using a 0.2% Pd / α Al₂O₃ catalyst. The data correspond to the experiments presented in Table 5.

[0181] Example 6

[0182] Diluting raw materials using inert gas

[0183] Example 6 demonstrates the beneficial effect of feed dilution with N2 as a diluent on improving product selectivity when converting 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using Pd / Al2O3 as a catalyst. The reaction and product analysis were performed using the same apparatus and procedures described in Example 1. 50 mL of 0.3% Pd / θAl2O3 catalyst was loaded into a tubular reactor and pretreated with H2 at 150 °C for one hour at 150 mL / min. Then, when 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and N2 (as specified in Table 6) were passed through the catalyst bed at the desired flow rate, the catalyst bed temperature increased to 167 °C–174 °C upon introduction of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), depending on the flow rate. The conversion and selectivity values ​​are listed in Table 7. In Table 6 below, "X" represents the mole fraction assuming ideal gas behavior.

[0184] Table 6

[0185] Raw material dilution effect evaluation experiment

[0186]

[0187] Table 7

[0188] Product distribution of 0.3% Pd / θ Al2O3 catalyst before and after feed dilution

[0189]

[0190] In Table 7, all experiments were conducted at 45 psig. The reactor bed temperature was 150 °C before the introduction of organic matter, and was raised to the specified temperatures in the table due to the exothermic reaction.

[0191] Comparative Example 6

[0192] Reaction without reactant dilution

[0193] Comparative Example 6 demonstrates the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) using 0.3% Pd / θ Al2O3 without feed dilution, as described in runs 1, Tables 6 and 7. The reaction and product analysis were performed using the same apparatus and procedures as described in Example 1. 50 mL of 0.3% Pd / θ Al2O3 catalyst was loaded into a tubular reactor and pretreated with H2 at 150°C for one hour. Then, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) was introduced into the reactor at a flow rate of 15 g / h while H2 was passed through the catalyst bed at 150 mL / min at 150°C. The feed gas composition was 82% H2 and 18% 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). Upon introduction of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), the catalyst bed temperature was raised to 171°C and then slowly increased to 174°C over the next two hours. As shown in Table 7 (Run No. 1), the conversion was 77.47%, and the selectivity for “R-143 + recyclable” was 82.14%. The total selectivity for undesirable byproducts was 17.85%. More specifically, the selectivity for R-142a was 5.46%, for ethane 5.55%, for R-160 2.46%, for R-143a 0.72%, and for R-152a 0.31%.

[0194] Example 7

[0195] Dilute with organic molecules

[0196] Example 7 demonstrates the beneficial effect of using 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) as a diluent to improve product selectivity when using Pd / Al2O3 as a catalyst to convert 1,1,2-trichloro-1,2,2-trifluoroethane (HFC-143).

[0197] Except that the diluent was 1,1,2-trifluoroethane (HFC-143), the experiment was conducted in the same manner as described in Example 6. Similar results were observed, including lower hotspot temperatures and higher combination selectivity for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) in the presence of each of these diluents, compared to the absence of any of these diluents. These diluents include HFC-41, HFC-32, HFC-23, HFC-152a, HFC-134a, HFC-125, HFC-254eb, HFC-254fb, HFC-245fa, HFC-245cb, HFC-245eb, HFC-236ea, HFC-236fa, HFC-227ea, and HFC-143. Lower selectivity was also observed for byproducts including 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethylene (HFO-1132a), 1-chloro-1,1-difluoroethane (HCFC-142b), 1-chloro-1,2-difluoroethane (HCFC-142a), and / or chloroethane (HCC-160).

[0198] Example 8

[0199] Combining catalyst dilution and feedstock dilution

[0200] The catalyst dilution processes of Examples 1-5 were combined with the feedstock dilution processes of Examples 6 and 7. Similar or improved results were also observed, including lower hotspot temperatures, higher combined selectivity for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and lower selectivity for byproducts including 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethylene (HFO-1132a), 1-chloro-1,1-difluoroethane (HCFC-142b), 1-chloro-1,2-difluoroethane (HCFC-142a), and / or chloroethane (HCC-160).

[0201] aspect

[0202] Aspect 1 is a method for producing 1,1,2-trifluoroethane (HFC-143), the method comprising: hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reacting it with hydrogen in the presence of a catalyst to produce 1,1,2-trifluoroethane (HFC-143), said catalyst comprising: a catalytic material comprising 0.1 wt% to 1.0 wt% of the catalytic metal supported on the support based on the total weight of the catalytic metal and the support; and a diluent material, wherein the amount of said catalytic material is 5 vol% to 70 vol% based on the total volume of said catalytic material and said diluent material.

[0203] Aspect 2 is the method according to aspect 1, wherein the amount of the catalyst material is 10% to 50% by volume, based on the total volume of the catalyst material and the diluent material.

[0204] Aspect 3 is the method according to aspect 1 or aspect 2, wherein the metal includes palladium.

[0205] Aspect 4 is the method according to any one of aspects 1 to 3, wherein the carrier comprises aluminum oxide (Al2O3).

[0206] Aspect 5 is the method according to any one of Aspects 1 to 4, wherein the diluent comprises a metal or a metal alloy.

[0207] Aspect 6 is the method according to any one of aspects 1 to 5, wherein the carrier is selected from α-alumina, δ-alumina, θ-alumina and γ-alumina.

[0208] Aspect 7 is the method according to any one of aspects 1 to 6, wherein the carrier comprises α-alumina.

[0209] Aspect 8 is the method according to any one of aspects 1 to 7, wherein the hydrogenation step is carried out at a temperature of about 100°C to about 300°C.

[0210] Aspect 9 is the method according to any one of aspects 1 to 8, wherein the hydrogenation step is carried out at a temperature of about 150°C to about 250°C.

[0211] Aspect 10 is the method according to any one of aspects 1 to 9, wherein the hydrogenation step is carried out at a pressure of about 10 psig to about 100 psig.

[0212] Aspect 11 is the method according to any one of aspects 1 to 10, wherein the hydrogenation step is carried out at a molar ratio of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to hydrogen of about 3:1 to about 15:1.

[0213] Aspect 12 is the method according to any one of aspects 1 to 11, wherein the hydrogenation step achieves a selectivity of more than about 20% for 1,1,2-trifluoroethane (HFC-143).

[0214] Aspect 13 is the method according to any one of aspects 1 to 12, wherein the hydrogenation step achieves a combined selectivity of more than about 80% for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b) and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a).

[0215] Aspect 14 is the method according to any one of aspects 1 to 13, wherein the hydrogenation step achieves a combined selectivity of less than about 20% for 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1-chloro-1,2-difluoroethane (HCFC-142a), and chloroethane (HCC-160).

[0216] Aspect 15 is the method according to any one of aspects 1 to 14, wherein the hydrogenation step is carried out over a contact time of about 1 second to about 60 seconds.

[0217] Aspect 16 is a method according to any one of aspects 1 to 15, the method further comprising the additional step of dehydrofluorinating 1,1,2-trifluoroethane (HFC-143) in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z).

[0218] Aspect 17 is the method according to aspect 16, the method further comprising the additional step of isomerizing cis-1,2-difluoroethylene (HFO-1132Z) to produce trans-1,2-difluoroethylene (HFO-1132E).

[0219] Aspect 18 is a composition produced by the method according to any one of Aspects 16 to 17, the composition comprising: trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 95% by weight based on the total weight of the composition; and 1,1,1-trifluoroethane (HFC-143a) present in an amount of less than 5% by weight.

[0220] Aspect 19 is the composition according to aspect 18, the composition comprising: trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 97% by weight based on the total weight of the composition; and 1,1,1-trifluoroethane (HFC-143a) present in an amount of less than 3% by weight.

[0221] Aspect 20 is the composition according to aspect 19, the composition comprising: trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 99% by weight based on the total weight of the composition; and 1,1,1-trifluoroethane (HFC-143a) present in an amount of less than 1% by weight.

[0222] Aspect 21 is a palladium metal catalyst that can be used to hydrogenate 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reacting with hydrogen to produce 1,1,2-trifluoroethane (HFC-143), the catalyst comprising: a catalytic material comprising 0.1 wt% to 1.0 wt% palladium metal supported on an alumina (Al2O3) support based on the total weight of the catalytic metal and the support; and a diluent material, wherein the amount of the catalytic material is 5 vol% to 70 vol% based on the total volume of the catalytic material and the diluent material.

[0223] Aspect 22 is the catalyst according to aspect 21, wherein the amount of the catalyst material is from 10% to 50% by volume, based on the total volume of the catalyst material and the diluent material.

[0224] Aspect 23 is a catalyst according to aspect 21 or aspect 22, wherein the support is selected from α-alumina, δ-alumina and θ-alumina.

[0225] Aspect 24 is a catalyst according to any one of aspects 21 to 23, wherein the support comprises α-alumina.

[0226] Aspect 25 is a catalyst according to any one of aspects 21 to 24, wherein the diluent comprises a metal or a metal alloy.

[0227] Aspect 26 is a method for producing 1,1,2-trifluoroethane (HFC-143), the method comprising: combining 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with a feedstock diluent to form a reaction mixture; and reacting the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the reaction mixture with hydrogen in the presence of a catalyst to produce a product mixture.

[0228] Aspect 27 is the method according to aspect 26, wherein the product mixture comprises 1,1,2-trifluoroethane (HFC-143), and the method further comprises the additional steps of: separating the 1,1,2-trifluoroethane (HFC-143) from the product mixture; and delivering the 1,1,2-trifluoroethane (HFC-143) to a reactant mixture.

[0229] Aspect 28 is the method according to aspect 27, wherein the reaction mixture comprises a molar ratio of 1,1,2-trifluoroethane (HFC-143) to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) of about 0.25:1 to about 10:1.

[0230] Aspect 29 is the method according to aspect 28, wherein the reaction mixture comprises a molar ratio of 1,1,2-trifluoroethane (HFC-143) to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) of about 0.5:1 to about 8:1.

[0231] Aspect 30 is the method according to any one of aspects 1 to 25, wherein the method is used simultaneously with the method according to any one of aspects 26 to 29.

Claims

1. A method for producing 1,1,2-trifluoroethane (HFC-143), the method comprising: Hydrogenation of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) via reaction with hydrogen in the presence of a catalyst to produce 1,1,2-trifluoroethane (HFC-143), wherein the catalyst comprises: A catalytic material comprising, based on the total weight of the catalytic metal and the support, 0.1 wt% to 1.0 wt% of the catalytic metal loaded on the support; and The diluent material, wherein the amount of the catalytic material is from 5% to 70% by volume, based on the total volume of the catalytic material and the diluent material.

2. The method according to claim 1, wherein the amount of the catalyst material is from 10% to 50% by volume, based on the total volume of the catalyst material and the diluent material.

3. The method according to claim 1 or claim 2, wherein the metal comprises palladium, and the diluent comprises a metal or metal alloy.

4. The method according to any one of claims 1 to 3, wherein the carrier is selected from α-alumina, δ-alumina and θ-alumina.

5. The method according to any one of claims 1 to 4, wherein the hydrogenation step is carried out at a temperature of about 100°C to about 300°C.

6. The method according to any one of claims 1 to 5, wherein the hydrogenation step achieves a combined selectivity of more than about 80% for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a).

7. The method according to any one of claims 1 to 6, wherein the hydrogenation step achieves a combined selectivity of less than about 20% for 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1-chloro-1,2-difluoroethane (HCFC-142a), and chloroethane (HCC-160).

8. The method according to any one of claims 1 to 7, further comprising the following additional steps: 1,1,2-trifluoroethane (HFC-143) was dehydrofluorinated in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z).

9. A composition produced by the method according to any one of claims 1 to 8, the composition comprising: Trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 95% by weight; and Based on the total weight of the composition, 1,1,1-trifluoroethane (HFC-143a) is present in an amount of less than 5% by weight.

10. A palladium metal catalyst, said palladium metal catalyst being used to hydrogenate 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reaction with hydrogen to produce 1,1,2-trifluoroethane (HFC-143), said catalyst comprising: A catalytic material comprising, based on the total weight of the catalytic metal and the support, 0.1 wt% to 1.0 wt% of palladium metal supported on an alumina (Al2O3) support; and The diluent material, wherein the amount of the catalytic material is from 5% to 70% by volume, based on the total volume of the catalytic material and the diluent material.

11. The catalyst of claim 10, wherein the amount of the catalyst material is from 10% to 50% by volume, based on the total volume of the catalyst material and the diluent material.

12. The catalyst according to claim 10 or claim 11, wherein the support is selected from α-alumina, δ-alumina and θ-alumina.

13. The catalyst according to any one of claims 10 to 12, wherein the diluent comprises a metal or a metal alloy.

14. A method for producing 1,1,2-trifluoroethane (HFC-143), the method comprising: 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is combined with a feed diluent to form a reaction mixture; and The 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the reaction mixture is reacted with hydrogen in the presence of a catalyst to produce a mixture of products.

15. The method of claim 14, wherein the diluting composition comprises a molar ratio of 1,1,2-trifluoroethane (HFC-143) to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) of about 0.25:1 to about 10:1.

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